Ha help please

[johnb]

So using the kit in my signature and a Ha filter I have some 30 mins worth of 300 sec exposures stacked in DSS and imported into PS, I expected it to be grey (not sure why ) anyway its very red.

So should it be red or gray and are there any special settings I should be using in DSS ?

regards

John B

[Steve Ward]

There's a really handy tutorial on DSS here . .

Hope it helps some . .

Steve.

[Astroblagger]

would like to ask afew questions in regards to this thread too, i was out last night taking images of the rosette nebula with my new clip in eos H Alpha clip filter and modded 450D i was expecting black and white images, as i see alot of other people get B&W images when imaging in H Alpha, so my question is do i set my camera to mono? when i read people talking about combining colour and H Alpha is this mainly people with mono ccd cameras? or can it be done with dslr's too? any help appreciated.

[Jessun]

The black and white images you mean are probably taken with a mono ccd.

This grey scale image can then be assigned a colour - Red. If you shot mono in your DSLR and then converted to red you'd probably end up back where you started with your image above.

(Having said this it should be noted that I don't have a mono CCD or a Ha filter but I'm pretty sure that's how it works.)

/Jesper

[johnb]

So reading a bit more I have a modded Cannon and without the filter it takes a combined RGB image, stick the filter on and its taking an Ha image

So once processed in DSS it shows read with a small amount of G and B see the pic.

I think then you can open this in PS and select chanells and just keep the Reg chanel and you will see the familar Gray pic which I think is representative of the Ha

The next step is to somehow merege than with an existing RGB image and map the grey to a colour (I think)

John B

[Tim]

You're getting there

I don't use the method very often, but I don't think a ha-G-B image looks especially great, you need to keep the red channel and merge the Ha data as a percentage for it to look "right".

That's as I understand it.

As for combining, the easiest way I have found is to use a program called Registar. It's not free, but it will happily merge images of different scales, mono or colour into one.

Also, it has the ability to merge to RGB to save you farting around, and you can also easily merge Red & Ha data as varying percentages and with various combination methods, and preview them there and then. It;s how I combine all my narrowband data and LRGB data. I think you can try it for free though??

THT

Tim

[johnb]

Ahh so the grey Ha images we see on the forum are typically CCD with no color mapping. For the Cannon lot we will have a RGB image add the filter and we have a Red image we then basically merge the two taking as much or as little of the Red from the Ha as appropriate.

John B

[Les Tilly]

if you use photoshop you take your red HA image and change the mode to grayscale and discard the color

i use registar to combine my ha into my red then combine in HARGB

[melsky]

Hi

After I've proceesed the Raw files In Photoshop I then go to the channel palette and do a "split channels" I then throw away the blue and green and just save the red for stacking.

I'm using a modded Canon 600D

Mel

Typical result http://stargazerslounge.com/topic/150870-cygnus-ha-50mm-widefield/